Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

The section "pcie_aspm=force" was added to fix an earlier regression; it's my understanding that this was supposed to be fixed around 3.4 or 3.5 (not sure which), and I just forgot to remove it. However, no one else here mentioned using it, so I there it is.

2) This only seems to affect folks with hybrid graphics, so: Is everyone here testing this with only the integrated graphics enabled (i.e. discrete chip is disabled in bios or through acpi)?

I'm bringing these things up because I'm not experiencing this issue with my setup; whether booting clean or waking from suspend, my temps are currently 33-41 degress celsius across four cores, all scaling properly. (i7-2720QM Sandy Bridge, Intel HD 3000 integrated graphics only, system completely up-to-date).

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

Ok, some more data points from me (X220)I've updated the BIOS to latest version (1.34).I've also figured out that the issue is independent from being docked or undocked, on AC or on battery.The issue seems also to be existent in 3.5.* which I didn't notice because I updated from 3.4 to 3.6 directly.

Sometimes a suspend/resume cycle seems to fix the issue.I also get the CPU Power Package warnings. In addition there are warnings about the buggy ACPI table but I don't think it's relevant.I can however, post a dmesg with suspend/resume if it's of interest.

In addition here's my (trimmed) pacman.log. If you see suspicious packages or want me to try something, please tell me.I'm going to downgrade the kernel later to 3.4. FWIW, if I feel like, I'll try to bisect.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

jrk wrote:

Ok, some more data points from me (X220)I've updated the BIOS to latest version (1.34).I've also figured out that the issue is independent from being docked or undocked, on AC or on battery.The issue seems also to be existent in 3.5.* which I didn't

This is strange... I've been using linux 3.5 with my x220 since arch fed it into the repo and haven't noticed this issue. However, it is present with linux 3.6. As I've downgraded to 3.5, I'll try to confirm if it affects me or not.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

The section "pcie_aspm=force" was added to fix an earlier regression; it's my understanding that this was supposed to be fixed around 3.4 or 3.5 (not sure which), and I just forgot to remove it. However, no one else here mentioned using it, so I there it is.

2) This only seems to affect folks with hybrid graphics, so: Is everyone here testing this with only the integrated graphics enabled (i.e. discrete chip is disabled in bios or through acpi)?

I'm bringing these things up because I'm not experiencing this issue with my setup; whether booting clean or waking from suspend, my temps are currently 33-41 degress celsius across four cores, all scaling properly. (i7-2720QM Sandy Bridge, Intel HD 3000 integrated graphics only, system completely up-to-date).

ASPM Power Regression was fixed long time ago and ported back and forth to probably all stable kernels. It is not required anymore.

I started noticing new power regression around 3.4 which have continued to increase and Sandy Bridge seems to be main hardware affected. I do have Optimus but I have disabled it in BIOS and been using power saving Intel HD 3000.

My current power usage is 12W and temp is 50C. Last night while copying some 80GB files to an external hard drive my system temperature spiked to 97C. I had a kernel panic. This seems to be very erratic.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

Did a naive bisect. I fetched linux-3.4.7 to linux-3.5.5 from arm.Tested 3.4.7, 3.5.3, 3.5.5 and 3.5.6 with multiple reboots and suspend/resume cycles.They all behave fine.There are also kernel version 3.5.7, 3.6.0 and 3.6.1 for which I do not have packages (3.5.7 and 3.6.0 never existed as pkg I think).Right now I'm compiling 3.6.0. *sigh*

Seriously, stuff like this makes think about switching to Mac (which I would never do) or *cough* Windows *cough*. Sorry, just venting off a bit.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

jrk wrote:

Seriously, stuff like this makes think about switching to Mac (which I would never do) or *cough* Windows *cough*. Sorry, just venting off a bit.

You're using a bleeding edge distro. Instead of going to a whole different OS, wouldn't it make much more sense to stay where you are, but dial back the bleeding-edge-ness by using a LTS kernel? There's two LTS kernels now (3.4 and 3.0), though Arch only packages the latter.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

The section "pcie_aspm=force" was added to fix an earlier regression; it's my understanding that this was supposed to be fixed around 3.4 or 3.5 (not sure which), and I just forgot to remove it. However, no one else here mentioned using it, so I there it is.

2) This only seems to affect folks with hybrid graphics, so: Is everyone here testing this with only the integrated graphics enabled (i.e. discrete chip is disabled in bios or through acpi)?

I'm bringing these things up because I'm not experiencing this issue with my setup; whether booting clean or waking from suspend, my temps are currently 33-41 degress celsius across four cores, all scaling properly. (i7-2720QM Sandy Bridge, Intel HD 3000 integrated graphics only, system completely up-to-date).

ASPM Power Regression was fixed long time ago and ported back and forth to probably all stable kernels. It is not required anymore.

I started noticing new power regression around 3.4 which have continued to increase and Sandy Bridge seems to be main hardware affected. I do have Optimus but I have disabled it in BIOS and been using power saving Intel HD 3000.

My current power usage is 12W and temp is 50C. Last night while copying some 80GB files to an external hard drive my system temperature spiked to 97C. I had a kernel panic. This seems to be very erratic.

Hmm, I can't see why else I might not be affected by this. And I figured ASPM probably wasn't a cause (haven't changed my syslinux config in a long time, obviously), I'm just trying to figure out what made my setup different from all of yours, since I'm using the same kernel and much of the same hardware everyone else is.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

Gusar wrote:

jrk wrote:

Seriously, stuff like this makes think about switching to Mac (which I would never do) or *cough* Windows *cough*. Sorry, just venting off a bit.

You're using a bleeding edge distro. Instead of going to a whole different OS, wouldn't it make much more sense to stay where you are, but dial back the bleeding-edge-ness by using a LTS kernel? There's two LTS kernels now (3.4 and 3.0), though Arch only packages the latter.

1. 3.0 is sluggish. 2. Systemd fails or doesn't play nice on 3.0. Haven't done anything to remedy this failure because of point #1.3. New power regression bug are introduced some where around 3.4 as reported in forum and arch bug tracker.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

WonderWoofy wrote:

You know all those i915 parameters you two are using? Check out

# systool -m i915 -av

I set all those things at first, because I wasn't sure what the setting of -1 meant in those cases. Apparently those things are defaulting to being on. For instance, the i915_enable_rc6 can be set to 0, 1, 3, or 7. 1 will enable rc6, 3 will enable rc6p also, and 7 will enable rc6pp in addition to the other two. But without setting it to 1 on my own, it actually sits in rc6p most of the time (which is a lower power state than rc6, and rc6pp is even lower).

So I think that all the rc6 setting will actually set it to use ore power than the default. Frame buffer compression appears to be on by default, as does semaphores. The only one I think you are having a real effect with is the lvds_downclock setting.

I am not 100% on this. But I noticed my Ivy Bridge machine actually uses less power when I don't set all that crap, though I have not tried the lvds_downclock parameter.

I don't understand the output from systool, to be honest. The output from modinfo suggests that "-1" is "use chip default" which I assumed meant that it would depend on the particular chip and therefore might or might not be enabled for my particular machine.

Note that I'm not questioning your conclusions - I'd just like to understand the nature of the evidence they are based on.

I can see why you *might* get better savings by not setting this stuff - if your chip defaults to something more economical than 1 for i915_enable_rc6, for example. (Or you set it to 7 - are you still doing that?)

EDIT: When I first set this stuff up, I definitely got power-savings. But that doesn't mean it is still the best option. Nor does it mean that nothing I did is detrimental...

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

I'm also suffering with this heat issue on 3.6.2-1-ARCH. My X220 can't be safely called a "laptop" now since it's running much hotter. I'm using no related /proc/cmdline arguments, but maybe I should revisit them.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

donniezazen wrote:

Gusar wrote:

jrk wrote:

Seriously, stuff like this makes think about switching to Mac (which I would never do) or *cough* Windows *cough*. Sorry, just venting off a bit.

You're using a bleeding edge distro. Instead of going to a whole different OS, wouldn't it make much more sense to stay where you are, but dial back the bleeding-edge-ness by using a LTS kernel? There's two LTS kernels now (3.4 and 3.0), though Arch only packages the latter.

1. 3.0 is sluggish. 2. Systemd fails or doesn't play nice on 3.0. Haven't done anything to remedy this failure because of point #1.3. New power regression bug are introduced some where around 3.4 as reported in forum and arch bug tracker.

Didn't want to make this thread ot. But donniezazen points it out quite well. 3.4 LTS would probably be nice. Or some kind of "stable" checkpoints for pacman, where you could just say "ok, the last checkpoint from one month ago, that was fine, so I'll just install all packages covered by that checkpoint".

I'm currently bisecting. It's a PITA though, compiling the whole kernel takes roughly one hour. I've thrown out the majority of device drivers where I'm sure I don't need it. Still takes an eternity to build.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

Hmm maybe I should try bisecting this too. I've customized the kernel config for my asus NB (built in modules at least for the . builtin hardware), and compiling this kernel will probably take about 5 min. or so on my core i7 desktop.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

ANOKNUSA is right regarding optimus. I bisected the kernel and (idk why) tried powerstat with 3.6.2. Atm I'm back again to ~8.5W. I think I ran after a red herring. The power regression I'm experiening has something to do with bumblebee/nvidia driver. Disabling the nvidia card with bbswitch and no nvidia kernel module installed seems to help. Guess the nvidia driver is at fault in my case. Sorry for the confusion.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

Note that the first option (rc6=1) was fine under 3.5.6 but under 3.6.2 only rc6=7 stops power draw from spiking up to 25W+ (operating at ~10W now).

Still watching this as I've noticed other strange behavior under 3.6.2.

I've done that, actually currently have that in my kernel line, but it's random whether it works or not. Sometimes it will work on boot and after a suspend cycle or two, not work on boot, but afte a suspend magically work, or just not work at all.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

More news:

This was posted in the Arch bug report, and it seems to be related to what we are seeing. If anyone here has experience using the patch on Arch, post something confirming or denying it's effectiveness. I'm going to try this out myself when I get to an outlet. Good luck, everyone.

Re: Kernel 3.6.2 Power Regressions (Sandy Bridge)

Note that the first option (rc6=1) was fine under 3.5.6 but under 3.6.2 only rc6=7 stops power draw from spiking up to 25W+ (operating at ~10W now).

Still watching this as I've noticed other strange behavior under 3.6.2.

I've done that, actually currently have that in my kernel line, but it's random whether it works or not. Sometimes it will work on boot and after a suspend cycle or two, not work on boot, but afte a suspend magically work, or just not work at all.

I'm confirming this too... I've had at least one power consumption spike again post resume. Can't consistently replicate but it's definitely not a solid fix.

Note that the first option (rc6=1) was fine under 3.5.6 but under 3.6.2 only rc6=7 stops power draw from spiking up to 25W+ (operating at ~10W now).

Still watching this as I've noticed other strange behavior under 3.6.2.

I've done that, actually currently have that in my kernel line, but it's random whether it works or not. Sometimes it will work on boot and after a suspend cycle or two, not work on boot, but afte a suspend magically work, or just not work at all.

I'm confirming this too... I've had at least one power consumption spike again post resume. Can't consistently replicate but it's definitely not a solid fix.

Blech. Back to 3.5 it is then.

Sadly, I think that's our only real option now. Time to add an IgnorePkg list...